CHAPTER II. 



MORPHOLOGICAL UNITY OF LIVING BEINGS. 



§ I. The cellular theory. First period: division of the organism 

 — ^5 2. Second period: division of the cell — Cytoplasm — 

 The nucleus — § 3. Physical constitution of living matter — 

 The micellar theory — § 4. Individuality of complex beings 

 — The law of the constitution of organisms.' 



The first characteristic of the living beings is 

 orgattisation. By that we mean that they have a 

 structure; that they are connplex bodies formed of 

 smaller aliquot parts and grouped according to a 

 certain disposition. The most simple elementary 

 being is not yet homogeneous. It is heterogeneous. 

 It is organized. The least complex protoplasms, 

 that of bacteria, for example, still possess a 

 physical structure; Kunstler distinguishes in them 

 two non-miscible substances, presenting an alveolar 

 organization. Thus animals and plants present an 

 organization, and it is sensibly constant from one end 

 to the other of the scale of beings. There is a 

 morphological unity. 



§ I. The Cellular Theory. First Period : 

 Division of the Organism into Cells. 



Cellular Theory. First Period. — Morphological 

 unity results from the existence of a universal 



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